Spacer pattern for capillary reservoir elements



Aug. `19, 1958 R. L sPAuLDlNG 2,847,976

' sPAcER PATTERN RoR CAPILLARY RESERVOIR ELEMENTS Filed Oct. 28, 1955 2Sheets-Sheet 1 FG. l'.

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l Ill l ll Ill A wup/v By All@ 1.9, 1958 R. l. sPAuLDlNG 2,847,976

l sPAcER PATTERN FoR CAPILLARY RESERVOIR ELEMENTS Filed oct, 28, 1955 2Sheets-Sheet 2 RA wvo/v0 .SPA ULD/Nei f/VVE/VTOR SPACER PA'ITERN FORCAPILLARY RESERVOIR ELEMENTS Raymond L. Spaulding, Janesville, Wis.,assigner to The Parker Pen Company, Janesville, Wis., a corporation ofWisconsin Application October 2 8, 1955, Serial No. 543,355

2 Claims. (Cl. 1Z0- 50) This invention relates in general to capillaryreservoir or ller-and-reservoir elements for writing instruments and inparticular to such elements having thin walls spaced apart by spacersprojecting from said Walls.

Cylindrical capillary iiller-and-reservoir elements of this type areknown wherein perforated thin Walls are spaced apart radially by spacersof either generally cylindrical or dome-like shapes.

These prior art elements have the disadvantage that, if the spacersare'relatively small and spaced relatively far apart, the thin wallsbend or sag at various places thereby preventing the walls from beinguniformly spaced apart a distance equal to the height of the spacers.The bent portions of the wall may partially or totally block or coverthe perforations in an adjoining wall and may also block a portion ofthe space between a pair of adjoining walls. The sagging or bending ofthe Walls thus impedes the flow of ink through the spaces, both axially(longitudinally) andradially (laterally) of the reservoir element.

These prior art elements also have the disadvantage that, if thecircular or dome-like spacers lare either increased in size or placedclose together, to provide sul`n`cient radial support throughout theelement for uniformly spacing the Walls by preventing sagging orbending, the ink storage capacity of the reservoir element isprohibitively decreased and the flow of ink axially (longitudinally) andradially (laterally) is prohibitively impeded.

It has been discovered in connection with this invention that theprovision of generally rectangular elongated spacers patterned properlyon the Walls overcomes the above disadvantages. If the spacers aredisposed with their elongate dimension parallel to the axis of thecylindrical element they present the least impedance to axial(longitudinal) ink ow but they then have the disadvantage of beingextremely diicult to radially (laterally) align to provide proper radialsupport for obtaining nonsagging walls and uniform wall spacing. If thespacers are disposed with their long dimension perpendicular to thelongitudinal axis of the element they can be conveniently radiallyaligned to provide proper support for obtaining non-sagging Walls anduniform wall spacing but they then have the disadvantage of presentingthe maximum possible impedance to the axial flow of ink.

All of the above disadvantages are overcome by this invention byproviding a plurality of generally rectangular elongated spacers withtheir elongated dimension lying on the walls acutely angularly of thelongitudinal direction of the element in a pattern which provideslateral support for obtaining non-sagging walls and uniform wallspacingand provides ink paths for the effective llow of inklongitudinally and laterally through the element.

lt is therefore an object of this invention to provide a capillaryreservoir element having perforated thin walls spaced apart laterally byspacers arranged on the Walls in a pattern which provides, Withoutsubstantially decreasing the ink storage capacity of the element,sufficient nited States Patent 2,847,976 Patented Aug. 19, 1958 andproper support for uniformly spacing the walls apart laterally throughthe spaces between walls.

Another object of this invention is to provide a capillary reservoirelement having thin walls spaced apart laterally by spacers arranged onthe Walls in a pattern such that the spacers may easily be alignedlaterally for uniformly spacing the walls and such that effective inkpaths are provided for the unimpeded flow of ink through the spacesbetween walls.

It is a further object of this invention to provide a cylindricalcapillary reservoir element having thin walls radially spaced apart byspacers arranged on the walls in a pattern which provides, Withoutsubstantially decreasing the ink storage capacity of the element, bothproper radial support for obtaining non-sagging walls uniformly spacedand for obtaining effective ink paths for f unimpeded ow of the inkthrough said spaces axially and radially of the element.

Objects and advantages other than those mentioned hereinbefore will beapparent from the following description when read in conjunction withthe accompanying drawings, in which:

Fig. l is a plan view of a sheet having spacers arranged thereon inaccordance with one embodiment of the inventlon;

Fig. 2 is an enlarged view of a portion of the sheet shown in Fig. 1;

Fig. 3 is a sectional view taken along line 3-3 of Fig. 2;

Fig. 4 is an isometric view illustrating how a capillary reservoirelement may be formed from a sheet such as is shown in Fig. l;

Fig. 5 is an isometric view of a capillary reservoir element embodyingthe invention;

Fig. 6 is a sectional view taken along line 6-6 of Fig. 5

Fig. 7 is a sectional view taken along line 7-7 of Fig. 5; and

Fig. 8 is a view, partly in section, embodying the invention.

Referring to the drawings, there is shown in Figs. l-4 inclusive, asheet 20 of perforated thin walledmaterial such as plastic or metal foilhaving secured thereto a plurality of generally rectangular elongatedrelatively rigid spacers 21 all projecting an equal distance (height)from the sheet, the sheet being capable of being spirally rolled uponitself to form a generally lcylindrical reservoir element 22, as shownby Figs. 5-7 inclusive, having uniformly radially (laterally) spacedconvolutions or walls 23 defning capillary ink storage spaces 24therebetween which extend axially (longitudinally) of the element. Thesheet has perforations 25 therethrough.

The axial or longitudinal direction of the reservoir element is shownhorizontally in Figs. 5 and 8, vertically in Figs. l and 2, andangularly in Fig. 4. The radial or lateral direction is shown verticallyin Fig. 8 and radially in Figs. 5, 6 and 7. The terms axially andlongitudinally are used herein interchangeably and are synonymous. Thesame is true with reference to the terms radially and laterally.

The spacers 21 may be of any suitable material such as plastic or metaland are preferably imperforate, the perforations preferably beingthrough the sheet proper, thereby eliminating the possibility of formingburrs thereof a fountain pen on thus 'better insuring that all thespacers will be of their intended height to thereby space the Walls 23the intended distance. The elimination of burrs on the spacers alsoeliminates ink and air traps being formed where the rough burred endskthereof would engage an adjacent wall.

To the end that the reservoir element 22 has laterally uniformly spacednon-sagging walls and has effective ink paths both laterally andlongitudinally'I ofthe element, the spacers 21 are rigid relative to thethin walls 23 and are arranged on the walls in a pattern particularlyadvantageous to these ends. The spacersare disposed in spaced apartrelationl leaving gaps therebetween so that the ink may'flow in theinterwa'll spaces in all directions. The spacers are spaced axiallyand'convolutely, and the inter-wall spaces are connected radially'byperforations 25 in the walls.V The'ink' can thus Yeffectively flowaxially (longitudinally),l convolutely (circumferentially) and radially(laterally).

The spacers 21 lie on the walls acutelyjangularly of the longitudinaldirection ofthe reservoir element 22 formed by the walls 23. Acutelyangularly'as used herein means at a finite acute angle less thanninetydegrees. The spacers are arranged to align intersectingly, as best canbe seen in Figs; 5 and 7. Intersect, intersecting and intersectingly` asused herein do not mean'actually tech- `nicallyinter'secting as twolinesmeeting at a common point but mean intersecting inthe'broader'sense asmore commonly understood, as an underground cable intersects a highwayand as a Vbridge intersectsa river, where two lines intersect althoughthey may be in different and parallel planes.

The spacers preferably lie at the acute angle of-fortytive degrees tothe'longitudinal axis of the velement and the spacers preferablyintersect perpendicularly, although satisfactory results can be achievedAwith acute angles other than forty-live degrees and with intersectionsother than perpendicular.

Fig. 6 electively'illustr'ates the radial (lateral) alignment of thespacers and further illustrates how the lengths of the spacers onadjacent walls progressively increasefrom the innermost'wall to 'theoutermost wall.

Fig. 7 clearly illustrates the intersecting alignment radially(laterally) and' shows the spaces intersecting perpendicularly.

Fig. l shows one manner of disposingthe spacers on a sheet to bespirally rolled upon itself to form a generally cylindrical capillaryller-and-reservoir element having radially spaced walls. The spacers 21are attached or secured to the sheet `in lany suitable manner and may beformed integrally therewith. The spacers are preferably all disposed onone side of the sheetthe inside of the sheet when spirally rolled asVshown in Fig. 4, to form the convolute, generally cylindrical reservoirelement shown in Fig. 5. The horizontal direction in Fig. l is referredto herein as the convolute or circumferential direction and the verticaldirection as the axial or longitudinal direction.

The spacers 21 are arranged 'in a plurality of parallel convolute rows.Each spacer in each convolute row is disposed one complete convolutionfrom a transversely disposed spacer so that when spirally rolled up, thespacers radially align intersecting'ly.r Each of the convolute rowscontains groups of spacers. Each of these groups extends convolutely onecomplete convolution and contains therein an equal number of spacersYspaced apart evenly convolutely. Thus when the sheet is spirally rolledinto the cylindrical form of reservoir element each spacer in each groupis in radial alignment with a corresponding spacer `in each adjacentgroup.

The spacers within each group are parallel to each other butperpendicular to the spacers within each adjacent group and thus, whenthe `sheet is rolled up, each spacer 21 on any one convolution or wall23 is not only in radial alignment with but also intersectsperpendicularly a corresponding spacer on each adjacent convolution orwall 23.

The convolute rows of spacers are spaced apart evenly axiallyand theperforations 25 are conveniently arranged in parallel convolute rowsintermediate the convolute rows of spacers.

The spacers in adjacent convolute rows are` staggered or unaligned so asnot to impede ow of ink axially (longitudinally) of the reservoirelement. This is accomplished by arranging the spacers so that thespacers in alternate convolute rows form parallel rows axially of theelement. This staggered or scattered pattern of the spacers allows theink to flow eiectively axially of the reservoir element through the ink-storage spaces.

Within each group in every row, the spacers are paralleland evenlyspaced convolutely a sufficient distance to prevent ink from forming ameniscus bridging two convolutely spaced spacers to thus impede or blockink ilow axially of the element. The convolute distance between groups,i. e. from the last spacer in each group to the first spacer in the nextgroup isalso of a sufficient distance to prevent such menisci and theattendant blocking of or impedance to axial ink flow.

The spacers in each convolute row increase in length from the innermostconvolution or wall 23 to the outermost convolution or wall 23, as theconvolutions themselves increase in convolute or circumferential length.The spacers on the inner convolutions need not be'as long as they mustbe on the outer convolutions to give the walls the rigidity and supportnecessary for uniform or even wall spacing. This'arrangement results ina reservoir element of more storage'capacity than would be the case ifthe same sized spacers were used throughout the element as were used onthe outermost wall, and also results in a saving of the material fromwhich the sapcers are made. As shown in Fig. l, the spacer lengthsincrease, group by group, i. e. the spacers within each group are all ofthe same length but of a different length than' the spacers within anyother group. The spacers, however, can be arranged to continuouslyincrease in length throughout each convolute row and need not increasegroup by group, or they can be arranged so that two or more adjacentgroups contained spacers of equal lengths but of different lengths thanthe spacers in groups convolutely disposed from said two or more groups.

One of the important advantages of having the spacers increase in lengthfrom the innermost convolution to the outermost convolution is that thisfacilitates the substantial radial alignment of the spacers during thewinding operation. Winding tolerances can thus be less strict than wouldbe the case if the spacers were all of the same length. Thus, eventhough the center points of the spacers are not perfectly alignedradially because of lack of perfection inthe practical manufacturingwinding techniques, the spacers will intersect at points other thantheir centers and still provide the necessary radial support for givingthe desired rigidity and wall to wall spacing. The deviations fromperfection in the winding technique are thus compensated for byproviding spacers of varying lengths, increasing in length from theinner convolution to the outer convolution.

The spacers may all be of the same height to thereby space all of thewalls the same distance apart, or the height of the spacers may bevaried group by group or continuously, in a manner similar to thatdescribed above for the length of the spacers, to accomplish aprogressively varying wall spacing throughout the reservoir element. Itmay, for example, be desirable to space the inner walls more closelythan the outer walls. The spacers are shown in Figs. 3, 6 and 7 as allbeing of equal height, but spacers of varying height are within thescope of this invention.

The height of the spacers of course must be such to provide thereservoir element with the wall spacing which obtains the necessary anddesired capillarity. The fillerand-reservoir element is designed so thatwhen used in a writing instrument it will have sufficient capillarity tofill itself by capillary action and to maintainink therein under allnormal circumstances but insuflicient to prevent withdrawal of inkduring writing. The width of the spacers should be as small as possibleso that the spacers do not unnecessarily decrease the ink storagecapacity of the reservoir element. The length of the spacers is selectedto give the necessary rigidity to the walls to aid in maintaininguniform wall spacing but not to interfere with the rolling operation informing the reservoir. Dimensions will depend to some extent upon thethickness of the walls and upon the materials used for walls andspacers. Dimensions which have proved satisfactory but are not to beconstrued as limiting the invention are as follows:

For a sheet of plastic material about .001 thick, spacers of plastic maybe about .017 wide, in the range of about .008l high, and may havelengths of about .050" for the spacers in the group on the innermostwall, the lengths increasing as above explained to about .125 for thespacers in the group on the outermost wall.

Fig. 8 illustrates a writing instrument such as a fountain pen embodyinga reservoir element constructed in accordance with the invention. Abarrel 26 and a shell 27 house the internal elements of the pen. Thereservoir element 32 is disposed within a casing 28 open at both ends.All the elements of the pen except the barrel are firmly secured to theshell. The barrel is removable from the casing and shell structure andwhen removed exposes the rear end of the reservoir element so that thereservoir element may be lled by capillary action by dipping the exposedrear end of the pen in ink. A writing element 29 communicates with thereservoir through a collector member 31 and a feed element 30. Thereservoir element 32 is of the type described herein above havinglaterally spaced walls forming longitudinally extending ink storage andtransfer spaces between the walls. The spaces provide for ow of inklongitudinally therethrough from the rear of the reservoir element up tothe collector member 31 at the front of the reservoir element.Perforations through the walls provide for the ow of ink laterallythrough the reservoir element from the outside wall thereof adjacent theinside of casing 2S to the feed element 30 disposed inside the innermostwall of the reservoir element. The spacers (not shown) are arranged onthe walls acutely angularly of the longitudinal axis of the element andthe spacers are in lateral alignment intersectingly. The walls thus areproperly supported laterally to uniformly space the walls and to preventsagging or bending. The spacers therefor function to provide elfectiveunimpeded paths for the flow of ink both longitudinally and laterallythrough the reservoir element to the collector member and to the feedelement. The ink finds its way from the feed element and collectormember to the writing element in a manner Well known in the art.

The invention is applicable to a cylindrical reservoir elementcomprising a plurality of radially spaced concentric tubes and is alsoapplicable to a reservoir element coniprising a plurality of flat wallsspaced laterally apart although such embodiments of the invention havenot been shown. ln the case of the laterally spaced flat walls, there isno need for spacers of varying length, but the other features of theinvention apply.

Features disclosed but not claimed herein are disclosed and claimed incopending application Serial No. 542,844, tiled October 26, 1955, ofJohn Dyson, assigned to the same assignee as is this application.

Although only one embodiment of the invention has been shown anddescribed, it will be apparent to those skilled in the art that othermodifications and variations may be made therein without departing fromthe spirit of the invention and the scope of the appended claims.

I claim:

l. A capillary iller-and-reservoir element for a writing instrumentcomprising a perforated sheet of thin walled material spirally rolledupon itself, a plurality of elongated spacers lying on Ione side of saidsheet spacing the convolutions thereof to dene between said convolutionsa spiral ink storage space extending axially of said element, saidspacers lying on said sheet at forty-tive degrees of the axial directionof said element, said spacers being arranged in parallel rowsconvolutely of said element, said convolute rows being spaced apartevenly axially of said element, said convolute rows having thereingroups of spacers, each group extending convolutely one completeconvolution of the sheet, each group having an equal number of spacerstherein spaced apart evenly convolutely, the spacers within each groupbeing parallel, the spacers in adjacent groups being perpendicular, inevery convolute row each spacer in each group being disposed onecomplete convolution from a corresponding spacer in each adjacent groupwhereby each spacer in each group is in intersecting radial alignmentwith corresponding spacers in every other group, the spacers within eachgroup being of equal lengths but being of different length than thespacers within any other group, the length of the spacers increasinggroup by group from the group on the innermost convolution to the groupon the outermost convolution, said element having sufficient capillarityto ll itself by capillary action and to retain the ink therein butinsuiicient to prevent withdrawal of ink in writing.

2, A capillary tiller-and-reservoir element for a Writing instrumentcomprising a perforated sheet of thin walled material spirally rolledupon itself, a plurality of elongated spacers lying on one side of saidsheet disposed thereon throughout its length and breadth spacing theconvolutions thereof throughout their length and breadth to definebetween said convolutions a spiral ink storage space extending axiallyof said element, said spacers lying on said sheet acutely angularly o'fthe axial direction of said element and being arranged in intersectingradial alignment so that the spacers on adjacent convolutions intersectthereby providing radial lines of support from the innermost convolutionto the outermost convolution and there by providing ink paths for theeffective flow of ink axially and radially of said element, said elementhaving sufficient capillarity to fill itself by capillary action and toretain the ink therein but insuiiicient to prevent withdrawal of the inkin writing.

References Cited in the tile of this patent UNITED STATES PATENTS

